Can metal halide wattage be changed ?

[Backreefing]

I have a question about metal halide bulbs can you take out a 250 watt bulb and put in less wattage like 175 ? Are they like light bulbs change a 100 for a 75 ? I would assume going down a step is ok but can’t go up without changing ballasts.

 

[Reeferdood]

You can downsize but it will shorten the life of the bulb, not a recommended practice.